import "StandardLibrary"
import "Minigraph"

main = withGraph do
    a = resource "a"
    b = map resource ["b0", "b1", "b2", "b3", "b4"]
    r = map resource ["r0", "r1"]
    
    enforce
        Statement a (r!0) (b!0)
        Statement a (r!0) (b!1)
        Statement a (r!1) (b!4)
        Statement a (r!1) (b!3)
        Statement (b!1) (r!0) (b!2)
    R a :- {}
    R ?x :- R ?y ; Statement ?y (r!0) ?x
    S ?x :- R ?x ; Statement ?x (r!0) _
    sort $ map uriOf $ select ?x where S ?x
--
[a, b1]